Lithium-ion polymer batteries are fabricated by various methods. In U.S. Pat. No. 5,536,278 an electrolyte film, previously prepared, is heated and laminated to a first electrode. The second electrode is then laminated to the laminated first electrode.
In U.S. Pat. No. 5,778,515 an electrode film and a separator film are formed then laminated after use of a pre-lamination solvent on the surface at least one of the films.
In U.S. Pat. No. 6,024,773 a separator film is coated on both sides with a binder resin solution so as to bond the electrodes with the separator film separating them.
In U.S. Pat. No. 5,348,824 polymer based amorphous compositions are melt extruded in the form of a thin film directly on the positive electrode of a lithium battery.
In all of the processes in which a sheet or film is formed, the composition of the separator material is limited to polymers having satisfactory mechanical strength for forming a thin film and for carrying out the laminating process with the electrodes. Use of particulate material in the polymer, to any great extent, is nearly impossible with any polymer as the mechanical strength is decreased further with the addition of the particulate material. In melt extended polymers, the porosity is difficult to control and is typically low.
Those disadvantages and other are overcome with use of the present invention.